Metal heat dissipating plate

ABSTRACT

A metal heat dissipating plate is provided. The metal heat dissipating plate includes a metal substrate, metal cladding layers, and graphite layers. The metal cladding layers are disposed on two surfaces of the metal substrate, and the graphite layers are intercalated into the metal cladding layers. Thus, the graphite layers can firmly bond to the metal substrate by the surface structure of the metal substrate and the metal cladding layer. The carbon film is made from graphite and thus has good thermal conductivity to increase the heat dissipating effect of electronic products and thus increase the service life thereof

BACKGROUND Field of Invention

The disclosure relates to a metal heat dissipating plate. More particularly, the disclosure relates to a metal heat dissipating plate with a good thermal conductivity, and the metal heat dissipating plate can be applied in various electronic products to reach a good heat dissipating effect.

Description of Related Art

With the rapid development of the electronics industry, the electronic devices, such as PCs, mobile phones, business machines, and GPS navigation devices, are more and more popular in the modern society. The volume of the electronic components and devices are increasingly thin, light, and small, as well as the functions thereof are more and stronger.

With the increasing integration of the electronic products, the number of the electronic components in a unit area is exponentially increased, and the heat dissipation becomes an important issue. If the heat cannot be dissipated in time, the working temperature of the electronic components will be increased. The electronic components will be failed in the serious cases to directly affect the service life and the reliability of the various high-precision equipment using these electronic components. Therefore, the heat dissipating problem has become a bottle neck of the miniaturization and integration of electronic products.

Conventional heat dissipation technology uses thermal conducting silicones. The advantages of the thermal conducting silicones is compressible. However, comparing with the metals, such as Cu, the thermal conducting rate of the thermal conducting silicones is too slow, and fans are thus usually required to be therewith. Therefore, in the situation of requiring fast decreasing temperature and limited space, the thermal conducting silicone becomes powerless. Accordingly, some uses a Cu foil and a carbon layer bonded thereunder for heat dissipation. Please see Chinese Patent No. CN 103476227A, “copper-carbon composite heat dissipating plate and a preparation method thereof”

A copper-carbon composite heat dissipating plate that is made of a copper foil and carbon thermally conductive layers coated on two surfaces of the copper foil. The thickness of the copper foil is 0.02-0.25 mm, the thickness of the thermally conductive carbon layer is 0.015-0.03 mm. The thickness of the copper-carbon composite heat dissipating plate is 0.08-0.3 mm. The carbon thermally conductive layers include 100 parts by mass of graphene or single-wall carbon nanotube (SWCN), and 1-50 parts by mass of an adhesive. The specific surface area of the graphene is 500-1000 m²/g. The particle diameter of SWCN is 5 nm. The adhesive is polyvinylidene fluoride, polyvinyl pyrrolidone, polyethylene glycol, polyvinyl alcohol, or a combination thereof.

A method of preparing the copper-carbon composite heat dissipating plate includes the following steps. (1) An adhesive is dissolved in an organic solvent to obtain an organic solution of the adhesive. (2) The graphene or the SWCN are mixed with the organic solution to obtain a mixture. (3) The mixture is dispersed by sonication for 0.5-1 hour, and then stirred at a stifling rate of 1500-3000 rpm for 1-5 hour to obtain a uniform mixture. (4) The uniform mixture is coated on the copper foil and then cured under an inert gas to obtain the copper-carbon composite heat dissipating plate. The curing temperature is 50-200° C., and the curing time is 10-100 min.

In the Chinese Patent No. CN 103476227A of “copper-carbon composite heat dissipating plate and preparation method thereof,” the carbon material can adhere to the bottom of the Cu foil, but the adhering method is preparing a carbon organic solution of the carbon material, the adhesive and the solvent, as well as coating and then curing the carbon organic solution under an inert gas to form the copper-carbon composite heat dissipating plate. Therefore, the carbon material is easily peeled off caused by the adhering way using only adhesive or solvent. The heterogeneous binding between the Cu foil and the carbon material is unstable, and the carbon layer is easily peeled off from the surface of the Cu foil. In addition, the way of binding the carbon material by the adhesive or the solvent can decrease the conductivity among the carbon particles to greatly decrease the thermal conductive effect.

Accordingly, in view of the drawbacks of the structure and method of combining the Cu foil and the carbon material leads to the decreased thermal conductive effect and high costs, the inventors improve the conventional heat dissipating plate by the many-year manufacturing and design experience and knowledge in the related fields and ingenuity.

SUMMARY

This invention is related to a metal heat dissipating plate with a good thermal conductivity. The metal heat dissipating plate can be used in various electronic products to obtain good heat dissipating effect.

The metal heat dissipating plate comprises a metal substrate, metal cladding layers, and graphite layers. The metal cladding layers are disposed on two surfaces of the metal substrate, and the graphite layers are intercalated into the metal cladding layers. Thus, the graphite layers with a high purity of carbon content 99.9% refined by petroleum can firmly bond to the metal substrate by the surface of the metal substrate and the metal cladding layer. The carbon film is made from graphite and thus has good thermal conductivity to increase the heat dissipating effect of electronic products and thus increase the service life of the electronic products.

In the metal heat dissipating plate above, the metal substrate is made from Cu, Al, stainless steel, or cold-rolled steel.

In the metal heat dissipating plate above, the surfaces of the metal substrate are smooth or rough.

In the metal heat dissipating plate above, the metal substrate has a thickness of 10 μm-1.6 mm.

In the metal heat dissipating plate above, the metal cladding layer is made from a metal of Ni, Cr, Ni—Cr alloy, Ag, or Ti.

In the metal heat dissipating plate above, the metal cladding layers and the graphite layers are formed by vacuum magnetron sputtering.

BRIEF DESCRIPTION OF THE DRAWINGS

The FIGURE is a cross-sectional diagram of a metal heat dissipating plate according to one embodiment of this invention.

DETAILED DESCRIPTION

To more completely and clearly illustrate the technical means and effects of this invention, the detailed descriptions are set forth below. Please refer to the disclosed figures and the reference numbers.

First, please refer to the FIGURE. The FIGURE is a cross-sectional diagram of a metal heat dissipating plate according to one embodiment of this invention. In the FIGURE, the metal heat dissipating plate comprises a metal substrate 1 having two opposite surfaces 11, two metal cladding layers 2 disposed on the two opposite surfaces 11, and two graphite layers 3 respectively intercalated into the two metal cladding layers 2. The graphite layers 3 are made from graphite with a high purity of carbon content 99.9% refined by petroleum.

The method of manufacturing the metal heat dissipating plate is described as follow.

First, a metal substrate 1 is provided, and the metal substrate 1 may be made from Cu, Al, stainless steel, or cold-rolled steel. The thickness of the metal substrate 1 is 10 μm-1.6 mm. The two opposite surfaces 11 of the metal substrate 1 may be smooth or rough according to the selected metal material. For example, when the metal substrate 1 is made from the unprocessed Cu, the metal substrate 1 may have smooth surfaces 11. When the metal substrate 1 is made from the unprocessed stainless steel or cold-rolled steel, the metal substrate 1 may have rough surfaces 11. Next, the metal substrate 1 is placed in a vacuum chamber. The vacuum chamber is used to provide a condition for performing vacuum magnetron sputtering, and hence the metal cladding layer 2 may be deposited by vacuum magnetron sputtering in the vacuum chamber.

In the step of sputtering the metal cladding layer 2, the selected metal may be Ni, Cr, Ni—Cr alloy, Ag, or Ti. Then, the metal cladding layers 2 are deposited on the opposite layers 11 of the metal substrate 1. Subsequently, the high-purity graphite layers 3 are intercalated into the metal cladding layers 2 under the same vacuum magnetron sputtering condition to complete the manufacturing of the metal heat dissipating plate.

Accordingly, the metal heat dissipating plate manufactured above can have a strong binding force between the graphite layers 3 and the metal substrate 1. In addition, since the graphite layers are made of bonded carbon atoms, the graphite layers themselves have an excellent adhesiveness and thus are not easily peeled off The graphite layers 3 are composed of high purity graphite, and thus the graphite layers 3 have good thermal conductivity and electrical conductivity. The metal heat dissipating plate of this invention can greatly increase the mechanical strength of a heat dissipating plate. Since the metal heat dissipating plate has good thermal conductivity, the metal heat dissipating plate can increase the heat dissipating effect of electronic products and electronic components to increase the service life thereof.

In light of foregoing, this invention has the advantages as follow.

1. In this invention, the metal heat dissipating plate is a metal substrate, which may have smooth surfaces or rough surfaces. The graphite can bond to the surfaces of the metal substrate through the metal cladding layer, and the graphite can intercalate into the surfaces of the metal substrate and the metal cladding layer to form a firm bonding with the metal substrate. Therefore, the graphite will not be easily peeled off to make sure the increase of the mechanical strength of the metal heat dissipating plate.

2. In this invention, the metal heat dissipating plate uses high-purity graphite having excellent adhesiveness and electrical conductivity. Therefore, the mechanical strength of the metal substrate can be greatly increased, and the good thermal conductivity can help the heat dissipating effect of electronic products and electronic components to increase the service life.

3. In this invention, the metal heat dissipating plate adopts a layered structure that the metal substrate has metal cladding layers and graphite layers effectively adhering on the two surfaces of the metal substrate, so that the use efficiency of the heat dissipating plate can be doubled to increase the yield and the industrial competitiveness of the metal heat dissipating plate.

4. The metal heat dissipating plate of this invention can choose the metal material to present smooth surfaces or rough surfaces to reach the effect of wide applicability and strong structure attachment. 

What is claimed is:
 1. A metal heat dissipating plate, comprising: a metal substrate having two opposite surfaces; two metal cladding layers respectively disposed on the two surfaces of the metal substrate; and two graphite layers respectively intercalated into the two metal cladding layers, wherein the graphite layers are made from graphite with a high purity of carbon content 99.9% refined by petroleum.
 2. The metal heat dissipating plate of claim 1, wherein the metal substrate is made from Cu, Al, stainless steel, or cold-rolled steel.
 3. The metal heat dissipating plate of claim 2, wherein the metal substrate has a thickness of 10 μm-1.6 mm.
 4. The metal heat dissipating plate of claim 3, wherein the metal cladding layer is made from a metal of Ni, Cr, Ni—Cr alloy, Ag, or Ti.
 5. The metal heat dissipating plate of claim 4, wherein the metal cladding layers and the graphite layers are formed by vacuum magnetron sputtering.
 6. The metal heat dissipating plate of claim 2, wherein the metal cladding layer is made from a metal of Ni, Cr, Ni—Cr alloy, Ag, or Ti.
 7. The metal heat dissipating plate of claim 2, wherein the metal substrate has smooth surfaces or rough surfaces according to the material of the metal substrate.
 8. The metal heat dissipating plate of claim 1, wherein the metal cladding layer is made from a metal of Ni, Cr, Ni—Cr alloy, Ag, or Ti.
 9. The metal heat dissipating plate of claim 1, wherein the metal cladding layers and the graphite layers are formed by vacuum magnetron sputtering. 